1. Field of the Invention
The present invention relates to a controller for a contact mechanism for bringing a contacting member into contact with a contacted member by moving the contacting member using an actuator.
2. Related Background Art
There is an already known contact mechanism for bringing a contacting member into contact with a contacted member by moving the contacting member using an actuator such as, for example, an automatic/manual transmission (automatic MT), wherein a motor or some other actuator is used to perform a select operation and a shift operation of a manual transmission, in which a power transmission is conducted between an input shaft and an output shaft of a vehicle by means of a select operation and a shift operation with a driver's manual operation.
In the shift operation of the automatic MT, the number of revolutions of a coupling sleeve is synchronized with that of a synchronized gear by moving a coupling sleeve rotating integrally with the input shaft to bring it into contact with the synchronized gear via a synchronizer ring, before bringing about an engagement between the coupling sleeve and the synchronized gear.
Moreover, there is known a technique of providing a buffering mechanism between a coupling sleeve and a synchronizer ring to protect an automatic MT mechanism and to reduce the time required for the shift operation and thereby absorbing a shock mechanically when the coupling sleeve contacts the synchronizer ring (for example, refer to Japanese Laid-Open Patent Publication (Kokai) No. 2002-195406).
The inventor et al. of the present application have already suggested a controller for a contact mechanism for changing a pressing force applied from a contacting member to a contacted member by varying an operational coefficient in a response specification type control for determining a control input to an actuator according to a difference between a target position and an actual position of the contacting member when determining the control input to the actuator by means of a position control that causes a position of the contacting member to follow the target position, in the contact mechanism bringing the contacting member into contact with the contacted member by moving the contacting member using an actuator.
In this type of controller, the position control is conducted to determine the control input to the actuator according to the difference between the target position and the actual position of the contacting member so that the target position of the contacting member matches the actual position thereof. The inventor et al. of the present application found that, with a low reaction force of the contacted member at the time of the contact between the contacting member and the contacted member and a small difference between the target position and the actual position of the contacting member, an output of the actuator becomes low and it causes a lack of pressing force applied from the contacting member to the contacted member.